| Cooling Type | Cooling Cap. kW | Est. PUE | COP | Max W/rack | CapEx Factor | Suitability |
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Our mechanical and electrical engineers design cooling infrastructure for data centres from hyperscale to edge — including CRAH, DLC, and immersion systems with full ASHRAE compliance.
The total heat load in a data centre is the sum of all heat-generating sources within the conditioned space. This includes IT equipment (the dominant source), UPS and power distribution losses, lighting, and solar/conduction gains through the building envelope. Each watt of electrical power consumed within the data hall is ultimately converted to heat that the cooling system must remove.
The fundamental equation is: Qtotal = QIT + QUPS losses + Qlighting + Qenvelope. UPS losses are calculated from efficiency: a 96% efficient UPS supplying 500 kW to IT equipment dissipates approximately 20.8 kW as heat. Lighting contributes directly. Envelope gains depend on building construction, orientation, and external temperature differential.
A safety factor of 10–15% is applied to the calculated load to account for future growth, measurement uncertainty, and peak transient conditions. The redundancy configuration determines the number of cooling units required over and above the calculated capacity.
Airflow rate (m³/h) is derived from the sensible heat equation: Q = V̇ × ρ × cp × ΔT, where ρ is air density (approximately 1.2 kg/m³), cp is specific heat capacity (1.006 kJ/kg·K), and ΔT is the supply-to-return temperature differential. ASHRAE A1 class facilities typically operate with a supply temperature of 18–27°C and a ΔT of 10–20°C.
For CRAH and chilled water systems, the chiller plant must be sized to reject the total data hall heat load plus the heat added by the chiller compressor itself. The Coefficient of Performance (COP) of the chiller determines the electrical power input: a chiller with COP 3.5 requires approximately 1 kW of electrical input per 3.5 kW of cooling output. At high ambient temperatures, COP degrades and chiller capacity must be derated accordingly.
ASHRAE Guidelines Reference: ASHRAE TC 9.9 Thermal Guidelines for Data Processing Environments define four equipment classes (A1–A4) with inlet temperature ranges from 15–45°C. Class A1 (enterprise servers): 15–32°C inlet. Class A2 (most servers): 10–35°C. Class A3/A4 (ruggedised): up to 40–45°C. Supply air temperatures should be set as high as the installed equipment class permits to maximise free-cooling hours and reduce mechanical cooling energy. NOVTRIQ designs cooling systems to ASHRAE Thermal Guidelines and EN 50600 data centre standards.
This tool provides indicative estimates. NOVTRIQ's mechanical engineers deliver detailed thermal modelling, CFD analysis, and cooling system design for data centres and critical facilities to EN 50600 and ASHRAE standards.
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